This invention relates to improvements in positive displacement fluid flow meters, and more particularly, to a combination reduced size meter housing and variable configuration inlet and outlet runners therefor.
Industrial fluid flow meters, such as those used in the petrochemical and liquified petroleum gas industries, are generally the reverse of a positive displacement pump. That is, the fluid, flowing through a commercial delivery system, whether it be a gasoline storage tank facility, gasoline transport truck, or other storage or delivery system, generally has a positive displacement meter connected in line in the fluid delivery system such that movement of fluid, whether gas or liquid, through the delivery line causes movement of the rotors in the meter which drives a mechanical or electrical counting device to precisely measure the movement of flow through the delivery system. A typical industrial meter is a plastic rotary fluid displacement meter suitable for use in the food industry is disclosed at U.S. Pat. No. 3,465,683.
In practice, when a chemical storage facility is constructed, a certain make of meters is chosen for use and the fluid delivery system is built around those meters. Likewise, when fluid transport trucks are built, the fluid delivery system constructed on the vehicle is engineered or designed to fit a specific make meter.
Generally, meters have a working life which is less than that of the installation or environment in which the meter is installed. Therefore, a meter in an industrial installation will ordinarily be replaced several times during the life of the storage or transport facility in which it is mounted. However, because of the specific construction of the environment in which it is mounted, the replacement meter must be of the same size as the meter that it replaces. Additionally, the orientation of the replacement meter must be such that the meter display is upright and readable when installed. Throughout industry it has been common for the replacement meters in these fluid storage facilities or transport vehicles to be the same make as the original equipment meter. Therefore, size and variability limitations of present day meters have not allowed the users to take advantage of increases in technology and longevity of life found in certain meters, when those installations did not originally have those specific meters engineered into them.
This lack of interchangeability of replacement meters in installations for which they were not originally designed is no more self-evident than found in differing world markets, and British and metric measuring systems such as between the United States and Europe or South America.
A need has developed for a combination industrial fluid-gas meter which is so reduced in size from presently known meters that meter and associated input and output ports can be made to match the location of the input and output ports of a variety of differing competing industrial fluid-gas meters.
A need has also developed for an industrial fluid-gas meter having increased efficiency of past design to reduce rotor shaft bearing load, and decrease slippage during phase transition of the displacement rotors.
It is, therefore, an object of the present invention, generally stated, to provide an improved fluid-gas meter assembly which is adaptable to fit in the space previously occupied by gas-fluid meters of differing designs having differing input and output port positions.